Dr. Goss was a cardiologist for 35 years and says he thrived on the high-energy environment.

"You never know who will walk through the emergency-room doors, but in cardiology, you can be sure their life will be in danger," says the former physician, who was affiliated with Presbyterian Hospital Center in Albuquerque, N.M., for most of his career.

When he retired at age 69, Dr. Goss began searching for an outlet where he could bring his particular talents to bear. A longtime collector of antique tomes, he hit upon the idea of "saving old books." He remembers thinking that the same skills needed in heart interventions would come in handy in bookbinding: precision, focus and perfectionism.

ENLARGE

Jerome E. Goss
Cynthia Egenberg

Jerome E. Goss

Age: 76 Home: Corrales, N.M. First/primary career: Cardiologist Current path: Antique bookbinding and repair Why this path: "A long love of books, and the need of an encore career with hands-on participation."

"From a doctor's standpoint, when I see a book with a broken spine, a wobbly hinge, or trouble with its cover, it's just like a person who needs to be treated; they still have a lot of life left in them," he says.

So Dr. Goss set out to learn bookbinding. He applied to a prominent training program in Glasgow, Scotland, only to learn that the class was full. The professor, though, made an exception for him.

"I guess I was the first 69-year-old doctor from New Mexico who wanted to come live in Scotland for a year to learn to bind books," he says.

Dr. Goss and his wife, Lorraine, packed their bags and traded the desert sun for the gloomy skies of Glasgow. "I learned from the best craftsmen in the world," he says.

Today, he runs Milagro Bookbinding, a one-man venture specializing in restoring leather books from the 1600s and 1700s. Using only hand tools, he works on books from 11 a.m. to 5 p.m. every day in a specially designed bindery studio on his property in Corrales, N.M. (He starts his day with regular exercise, after a lifetime of distance running.)

Dr. Goss says he has built up a steady clientele of book collectors and dealers who value his attention to detail and willingness to scout out rare materials. Recently he took a trip to Florence, Italy, just to buy marbled paper.

Among his most interesting projects: a set of French dictionaries from 1691. The books were in bad shape; part of the work involved creating new leather spines. Only after he had completed his work did he learn that the books were valued at $80,000.

Gem of an Idea For a Business

Lee Gelb, a former executive at Starbucks Corp., has combined her experience at nonprofits with her business acumen to start a new chapter: running a company with a social bent.

"I took my passions and turned them into my livelihood," says the 56-year-old entrepreneur, who lives on Vashon Island, near Seattle.

Ms. Gelb's path has been anything but predictable. She grew up in the suburbs of New York but became interested in farming and enrolled at the University of Arizona's agriculture school. Later, with a master's in nutrition from Columbia University, she joined the global development program of CARE International. She spent more than a decade in Belize, Bangladesh, Sri Lanka and Haiti, and ended up in Seattle.

In 1997, she was recruited by Starbucks to create an international human-resources organization. Starbucks was expanding rapidly, and Ms. Gelb was thrown headfirst into the business world.

Then, seeking more time with her son, and wanting to put on an entrepreneurial hat, Ms. Gelb in 2002 became a human-resources consultant. But consulting ended up being more than a full-time job, and in 2005, Ms. Gelb decided to change course completely.

She approached a friend about starting a retail jewelry business, something that would combine her main interests—travel, design, jewelry, meeting new people, nonprofit work—into one company.

The result is Zavida Gemstones, a socially responsible business that buys and sells stones and handmade jewelry from countries such as India, Bangladesh, Thailand, Mexico, Indonesia and Ecuador, and returns 25% of its earnings to nonprofit groups. One of those is the Khamir Craft Resource Center, an organization in India that helps artisans in the Gujarat region create sustainable businesses.

Ms. Gelb says it was difficult to launch her business during the recession, but Zavida now has two employees and turns a small profit selling jewelry online, in galleries and at corporate offices. She handles everything from website design to merchandising, marketing and sales.

But she also gets to do things she loves, like designing, traveling to find new artisans and gemstone producers, and working closely with the India nonprofit.

"I travel to Gujarat every year to work with the families making products for Zavida, and that's so rewarding," says Ms. Gelb. She also enjoys trekking up mountains or entering remote areas to find new artists doing metal or gem work.

Ms. Gelb wants to sell her jewelry in more galleries and shops, and to expand the nonprofit portion of her business. "We are hoping to help artisans right here in the U.S.," she says. "There is so much need in our own country."

Career in Math Yields to Paris

Stephen Solosky first visited Paris when he was in his mid-40s—and promptly fell in love. In the past decade, he has visited the City of Light more than 50 times.

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Stephen C. Solosky
Linda Sloan

Stephen C. Solosky

Age: 55 Home: Great Barrington, Mass., and New York First/primary career: Math professor Current path: Travel writer and tour guide Why this path: "I always planned to pursue another career when I retired from teaching. I like writing and doing tours to introduce people to travel they wouldn't normally do on their own."

"Paris is a city of discovery for me," says Mr. Solosky, 55. "Every time I go, I find a new corner. It never gets old."

When he retired in late 2010 from a 31-year career as a math professor at Nassau Community College in Garden City, N.Y., Mr. Solosky knew he wanted to build some type of part-time business around his passion for Paris. Over the years, he had taken meticulous notes on Parisian sights, restaurants, neighborhoods and museums, and had turned those notes into a book, "The Traveling Professor's Guide to Paris," published in 2009. Yet it wasn't until friends and readers of his book started asking if he would accompany them on trips to Paris that Mr. Solosky hit upon the idea of leading tours.

As soon as he retired, he started Traveling Professor, a company that takes groups of as many as 12 people to Paris, Italy and Peru.

"I started with Paris, because that's the city I know best. But people loved the tours and asked if I could do other countries, too," says Mr. Solosky, who is planning to add Spain this year. He runs about six trips a year, and recently signed up two other professors to help him expand the business.

Many of his clients have never traveled abroad before, and Mr. Solosky enjoys teaching them about the history and culture of the cities they visit, as well as introducing them to his local friends.

Mr. Solosky's second act is something of a surprise to him. He has lived his whole life on Long Island. But when he divorced 10 years ago, he felt compelled to start traveling the world. Most trips find him in Europe, but he has also traveled extensively in Peru and Bolivia, where he's involved in a long-term volunteer mission to aid local communities.

Mr. Solosky makes one exception to this on-the-go lifestyle: He doesn't travel during the summer. He spends those months at his lake house in Great Barrington, Mass.

The tour business provides supplemental income, but Mr. Solosky says what really enabled him to "live his dream in retirement" was careful saving and a bit of luck. He started socking money away at age 18, lived frugally and receives a pension from his teaching job.

"I want to start spending more of my time helping others," says Mr. Solosky, who says he will favor volunteering in overseas locales. "I just can't sit still."

Out of Africa, Into Helping

Wanjiru Kamau will never forget the shock of arriving in Corvallis, Ore., from Kenya—moving as a 20-year-old student to a foreign land.

ENLARGE

Wanjiru Kamau
Civic Ventures

Wanjiru Kamau

Age: 70 First/primary career: University administrator/adjunct professor Home: "I live in Maryland, but I consider Kenya my home." Current path: Founder and executive director of African Immigrant and Refugee Foundation Why this path: "I find joy in empowering people to solve their problems."

"Leaving my family and my country, coming to a place where I knew no one, that was the most difficult but also the most exciting thing I've done in my life," says Ms. Kamau, now 70. She remembers finding common things, such as shopping at the grocery store, strange.

Ms. Kamau grew up in rural Kenya on a small farm, working the land with her mother and two sisters. Her father died when she was a baby. Pushed by her mother to pursue an education, she worked hard at her studies and was eventually offered a chance to attend college in the U.S. in 1960.

"I wasn't scared to come to the U.S., because my mother taught me to be strong," says Ms. Kamau. As a girl, she learned to farm, cut trees, slaughter goats and help run the finances for her family's 15-acre farm, while also walking miles to and from the local schoolhouse each day.

Ms. Kamau eventually earned degrees from San Jose State University and Pennsylvania State University. She spent several decades back in Kenya working at the University of Nairobi and raising four children. She returned to the U.S. in 1988 to pursue a Ph.D. and later worked as an adjunct professor at Penn State.

She also met many African immigrants who struggled to adjust to their new lives. Many were refugees, bewildered, illiterate, and unsure of how to find housing or register their children for school.

"I had to help them," says Ms. Kamau. "I asked myself, 'Why did I get all of this education if not to help people?' "

So in 2000, Ms. Kamau resigned from Penn State, withdrew $10,000 from her retirement account, and moved to Washington, D.C., to start a nonprofit organization called African Immigrant and Refugee Foundation. The organization provides African immigrants such assistance as mental-health services, English classes, tutoring and cultural clubs for children, and help resolving conflicts in domestic-violence disputes.

"People come to us injured in some way, and we help anyone with any problem," says Ms. Kamau, who adds that she received two calls just that day from women having problems with their violent husbands, and another from someone needing help filing asylum papers. "My phone rings off the hook at all hours," she says.

Since 2000, Ms. Kamau's foundation has provided help to more than 6,000 immigrants from 45 African countries and has given cultural training to more than 2,500 school counselors, caregivers, and others who work with African immigrants.

Ms. Kamau has no official employees, but she does hire consultants. She works more than 10 hours a day—fielding requests from immigrants, fund raising and planning for her organization's annual conference.

"There are times when money is tight, and I'm up at 3 a.m., that I feel I can't keep up this pace," says Ms. Kamau, who swims and eats a vegetarian diet to stay healthy. "But then I see a child's smile, and I get energized to keep going."

Second Acts looks at the many paths people are taking in their 50s and beyond. Kristi Essick, the author of these profiles, is a writer in California. You can reach her, and let us know how you're starting over in later life, at next@wsj.com.

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